日本では，2011 年からA2L 冷媒を使用した機器のリスクアセスメントを行い，安全運用の方法を確立して順次製品展開を行っているが，キガリ改正を受け，さらにGWP の小さい冷媒への転換が望まれている．GWP の小さい冷媒には，LFL が小さく燃焼性が強いA3 冷媒が多い．そこで，日本冷凍空調工業会ではA3 冷媒を使用した内蔵ショーケースのリスクアセスメントを行った．本論文ではA3 冷媒でも着火確率を精度よく計算できる計算方法を提案し，可燃空間を定量化するために行った冷媒漏えい解析，リスクアセスメントの詳細及び作成した日本の規格について説明する．

マルトビオン酸Ca は溶解性の極めて高い難消化性の酸性オリゴ糖Ca 塩であり，様々な食品への利用が期待されるが，食品の物性に及ぼす影響については十分に調べられていない．本研究では，マルトビオン酸Ca が冷蔵米飯の老化に及ぼす影響を調べた．レオメーターを用いた圧縮試験において，冷蔵米飯は保存時間の経過によって澱粉が老化し，圧縮荷重は高くなった．しかしマルトビオン酸Ca の配合によって澱粉の老化は抑制され，圧縮荷重の上昇は抑えられた．示差走査熱量計を用いた澱粉の再糊化エンタルピー測定においても同様の効果を示す結果が得られた．マルトビオン酸Ca による澱粉の老化抑制効果はマルトビオン酸イオンによる水素結合形成と，Ca イオンによる静電的相互作用とによってもたらされると考えられる．

"Freezer burn" is a type of quality degradation that occurs in frozen foods during frozen storage, which includes drying, degeneration, and discoloration. It is considered to be a sublimation phenomenon caused by a change in water vapor pressure due to temperature variations; however, there have been no studies regarding freezer burn in frozen pasta. In this study, the development of freezer burn in frozen pasta was visually monitored using a cryo synchrotron radiation X-ray computed tomography method. Using this approach, the state of freezer burn in the pasta was successfully visualized without sample pretreatment. The study revealed that temperature changes during storage accelerated the loss of moisture in frozen pasta. This was enhanced by increasing the frequency and amplitude of the temperature change. These results strongly indicated that, in order to suppress freezer burn of frozen pasta, storage freezers must be designed to suppress temperature changes.

水－臭化リチウム系の作動媒体を用いた吸収冷凍機では，出力温度を低温化するために蒸発器内の冷媒に臭化リチウムを混合して希薄溶液とし，凍結温度を0 ℃以下とする方法が用いられている．本研究では，この方法を一般的な温水焚一重効用吸収冷凍機に適用し，1～3 ℃程度の低温を発生する中低温吸収冷凍機の開発を目的とする．本論文ではその基本段階として，希薄溶液の特性を考慮したサイクルシミュレーションおよびデューリング線図によりその挙動を検討した．その結果，適正な希薄溶液濃度を設定することにより，蒸発器内の凍結温度，吸収液系統の結晶化濃度に対して十分な余裕を持つ冷凍サイクルが構築可能であることを示した．

排熱の有効利用を目的として，作動媒体を水－臭化リチウム系，蒸発器内を希薄臭化リチウム水溶液として1～3℃程度の低温を発生する中低温発生型吸収冷凍機を開発した．本論文ではその実用化段階として，製品規模の試作機を製作し，冷水出口温度を約1～3℃としてサイクルの性能および動作を検証した．その結果，加熱用温水温度90℃，冷却水温度28℃において成績係数(COP)は0.71～0.73程度であり，冷媒の凍結などの問題は発生せず，実用可能な信頼性を有することを確認した．また，本実験と同等の条件をシミュレーションした結果，これらは冷凍能力および入熱量について±5%，COPについて±0.005の範囲で一致した．

本研究では，ごみ焼却排熱を離れた需要地まで輸送して利用する技術として，溶液輸送型吸収冷凍機（STA）に着目した．アンモニア吸収冷凍機の発生器・凝縮器を排熱源側に，蒸発器・吸収器を需要側に設置し，その間をアンモニア冷媒液・アンモニア水溶液を輸送することによって熱輸送を実現する．また，溶液をタンクに貯めることで蓄熱機能も実現する．この技術と従来技術を考慮したエネルギーモデルを作成し，システムコスト最小化の観点から最適な技術構成を導いた．その結果，標準的と想定されるプラントコストにおいて，輸送距離6kmまでSTAが利用されること，プラントコストが2倍でもSTAは競争力を有することが示された．排熱有効利用を推進する上で，吸収溶液輸送・貯蔵を取り入れたSTAは有効と期待される．

A crossflow desiccant coated heat exchanger (CF-DCHE) driven by temperature swing adsorption based on direct hot water heating and evaporative cooling utilizing residual hot water was experimentally investigated. The time-averaged amount of dehumidification was examined as a key performance indicator while varying the primary operating parameters, including the cooling air velocity, process air velocity and regeneration/dehumidification cycle switching time. The results indicate that the adsorption outlet air humidity was decreased while the minimum humidity at the beginning of the adsorption period was decreased as the cooling air velocity was increased. After a certain period of time, the evaporation of water proceeded at a high rate and isothermal conditions were approached as adsorption progressed. The data also show that dehumidification performance was significantly affected by both the cooling air velocity and the cycle switching time. At shorter cycle switching times, the cooling air velocity had an effect on the time-averaged amount of dehumidification, but this phenomenon disappeared at longer cycle times under the present test conditions. When using the optimal switching time, the time-averaged amount of dehumidification increased along with the process air velocity in the case that cooling air was supplied.

With the increase in energy consumption, energy-saving attracts lots of attention. The desiccant dehumidification system is a potential substitute for the air-conditioning system that can achieve energy saving by decreasing the energy input for latent heat. Besides, the desiccant dehumidification system can further utilize the low-temperature heat waste in the desorption process. Thus, this study has focused on the low temperatures range between 40ºC and 70ºC on the desorption process with low humidity ratios of dry air as 0.005 kg/kg. The results indicate that, with the increasing desorption temperature, the water removal amount also increases, which means the ability of dry air to capture moisture from desiccant increases with higher temperature. At the desorption temperature of 68ºC, the average moisture removal capacity reached the peak, 0.0081kg/kg. Conversely, the coefficient of performance (COP) of the desorption process presented a downward trend with increasing desorption temperature. At desorption temperature 41ºC the COP is highest at almost 0.8, then gradually dropped to around 0.51 at desorption temperature 68ºC. The optimal desorption temperature can be determined as 54ºC.

13X ゼオライトの充填層を用いた吸着式ヒートポンプに飽和湿り空気を流通することで，高温水蒸気の生成を試みた．湿り空気温度を30 °C から 70 °C まで変更した条件で発生した水蒸気の最高温度を測定した結果，湿り空気を 70 ℃ まで加熱することで水蒸気の最高温度は 150 ℃ 以上となった．水蒸気の最高温度は湿り空気の空塔速度には大きく影響されなかったことから，ゼオライトと湿り空気間の熱伝達が水蒸気の最高温度に与える影響は小さいことがわかった．そこで，湿り空気とゼオライトの温度が等しいという仮定の下で，熱収支および吸着平衡から水蒸気の最高温度を推算した．その結果，湿り空気温度が高温の条件ではこれらの関係から最高温度を推算可能であることがわかった．

Nanotailored microporous silica represents one of the more recent artificially prepared advanced materials used in heat transformation and conservation field after silica gel and various zeolite and zeolite-like materials. In this work, we introduce experimental findings on the energy characteristics of water adsorption on nanotailored microporous silica with 1.5 % aluminium doping in the structure. The downscaled system in this work simulates actual working conditions in a controlled environment for both heating and cooling mode. The key properties of this material lie in the regeneration temperatures 60 to 80 ℃ and COP, which reaches values around 0.6 in case of cooling and 0.7 in case of heating. In absolute values at ΔT = 15 ℃, the system reaches storing capacities of about 90 Wh and 126 Wh per adsorbent kilogram in terms of cooling and heating potential energy, respectively. An important factor of kinetic influence on system performance is discussed on a basis of constant time experiment and time-dependent energy flow breakthrough analysis. Constraining factors are found to be in parallel through the driving force of the pressure swing as well as the heat transfer through the body of the adsorption bed.

Water vapor adsorption on activated carbon (AC) for dehumidification purposes has gained much attention due to the abundance of benefits provided by AC. The working region limited in high water vapor relative pressure (P/P0) makes this material suitable only for removing water vapor at a highly humid region. In this study, ozone oxidation was conducted to introduce more oxygen-based functional groups on AC to attract more water molecules. Based on surface characterization results, ozone oxidation increases oxygen functional groups such as carboxylic on AC but decreases their pores. The more AC exposed to ozone, the more different properties could be observed. The increment of functional groups enhances the water vapor adsorption uptake at P/P0 ≤ 0.6, shifting the water sorption into lower P/P0.

The purpose of a heat transformer cycle is to extract heat at high temperature by utilizing waste heat at low temperature level. The heat generated during the adsorption of high-pressure water vapor raises the temperature of the external fluid to be used flowing in the adsorption reactor. However, since the heat input during preheating of the reactor and the heat removal during precooling are large, therefore, the heat capacity seems to affect the performance. In this study, first, thermodynamic analysis of the equilibrium cycle was performed to predict the amount of extracted heat from a low heat capacity reactor. The heat capacity was 20% smaller than that of the conventional reactor, and as a result, the output heat was 20% higher. Therefore, it was clarified that the decrease in heat capacity directly led to an increase in output heat. In addition to reducing the heat capacity, the effect of improving performance by heat recovery was also significant. The effect was almost the same as obtaining the upper limit of the output heat achieved by zeroing the heat capacity of the reactor. Moreover, from the viewpoint of exergy, heat recovery was important to enable high temperature extraction.